Study The Effect Of Minocycline On Murine T Lymphocytes Behavior And Immunoregulation In DTH

Aim:To investigate the effect of Minocycline(MNC) on T Lymphocyte behaviors and DNFB-induced DTH,in order to explore the mechanism of immunoregulation effect of MNC.Methods:Fluorescence conjugated monoclonal antibodies and flow cytometry were used to detect the expression of CD69 on T lymphocytes activated by ConA to analyze its effect on activation. CFDA-SE staining together with flow cytometry was used to examine the proliferation of T lymphocytes.The distribution of the cell cycle was analyzed by PI staining together with flow cytometry.Fluorescence conjugated microbeads and flow cytometry were used to detect phagocytosis.NO production from macrophage was detected by Griess kit.Apoptosis induced by DEX of thymocytes were detected by Calcein-AM staining together with flow cytometry. Delayed type hypersensitivity(DTH) mouse model was established by stimulation with dinitrofluorobenzene(DNFB).MNC was injected intraperitoneal injection(i.p) for a week.The effect was observed by body weight,spleen index,swelling rate of pathogenetic ear and response of lymphocytes to ConA to illuminate the immunoregulation of MNC in vivo. Results:MNC could reduce the expression rate of CD69 and inhibit proliferation of activated T cells in response to ConA or PDB plus Ion.Flow cytometry analyse of cell cycle distribution revealed that MNC decreased the number of S and G2/M phase and increased the number of G0/G1 phase. MNC reduced significantly the apoptosis induced by DEX of thymocytes.MNC could promote resting macrophage phagocytosis of microbeads,but inhibit NO production stimulated by LPS.MNC had no influence on body weight of mouse,but it could significantly decrease the immune response of lymphocytes to ConA and swelling of pathogenetic ear of DTH mouse.Conclusion:MNC has significantly effect on behaviors of murine T lymphocytes.That indicated MNC has evident immune suppressive effect.It inhibited specific cellular immune response.MNC could dual-directionaly regulate function of macrophage.MNC could inhibit apotosis of lymphocytes.MNC weaken immune response of DTH mouse.This effect in vivo is coordinate in vitro.The pharmacological effects of MNC in vivo and in vitro may conduct through the same pathways and relate to the cells' entironment.It suggests MNC could treat some desease which is associated with immunity.